In electric energy stores, devices for a voltage supply of motor vehicles such as electro vehicles or hybrid vehicles, usually known as batteries. In most cases, a plurality of battery modules is employed that use electrochemical principles of oxidation with an electrolyte, thereby producing heat losses.
A stack of individual battery modules is clamped, oftentimes, over a mechanical end plate and tie-rods to build the energy store. In addition to mechanical fixation of the modules to each other, the end plates and the tie-rods serve to counteract deformations caused by gas pressure changes occurring when operating the battery modules.
Battery modules require cooling in order to ensure the necessary operational temperature. Typically, excess heat is dissipated via a heat exchanger, also known as battery cooler. In hybrid vehicles, the battery cooler can be connected to a coolant circuit of an engine, and in electro vehicles, the battery cooler can be connected to a refrigerant circuit of an HVAC system.
In prior art, the battery coolers, or battery cooler pipes, respectively, are directly bonded to the batteries or forced against the battery modules over a battery casing.
In DE 102010038600 A1, for example, a cooling system for a battery module is described. The cooling system is provided with a spring system that forces the cooling system flat against a bottom of the battery module. The spring system is arranged between a battery casing and the cooling system, and supported against a bottom of the battery casing.
In EP 2337142 A1 a cooling system for a battery module is described. The cooling system includes a flat contact plate. The contact plate is resilient and pre-stressed, urging the contact plate against a bottom of the battery.
In DE 102010029872 A1 a cooling system for a battery module is described. The cooling system includes several clamping elements which force a flat cooling body to a bottom of the battery modules.
Generally, the current concepts for forcing the battery cooler to the battery modules require significant installation space are very heavy, strongly contributing to a total weight of the battery.
It is an objective of the invention to produce a simple, lightweight, and cost-effective battery cooling system, which is capable of cooling the battery modules while minimizing a required installation space.